In a stator of a rotary machine such as a motor or an electric generator, a stator core and a coil are electrically insulated. For example, in Patent Literature 1, a stator is disclosed. This stator has a stator core which a plurality of divided cores are connected in an annular ring. A drive coil is wound around to the divided core via a first insulator and a second insulator which are disposed on both sides in a motor axis line direction. Each divided core is covered by a sheet-like third insulator. The drive coil is wound around on the third insulator. The third insulator is a slot insulating paper which is substantially rectangular-shaped. The third insulator is provided with, at an end portion of a circumferential direction, a projecting portion which is projected from the end portion of the circumferential direction of an outer peripheral side circular arc portion of the divided core to both the circumferential direction and the motor axis line direction. In configuring the stator, a salient pole side surface of the divided core, an inner peripheral surface of an inner peripheral side circular arc portion and an inner peripheral surface of the outer peripheral side circular arc portion are covered by the third insulator. Thereafter, the first insulator and the second insulator are overlaid from both sides of the motor axis line direction of the divided core. Both side portions of the motor axis line direction of the third insulator are in a state of being clamped between each surface of the salient pole of the divided core, the inner peripheral side circular arc portion and the outer peripheral side circular arc portion and, each portion of the first insulator and the second insulator.
In Patent Literature 2, an insulation structure of a motor iron core and a winding wire is disclosed. In this insulation structure, insulators are mounted on both ends in an axial direction. The insulator is molded to cover a certain length of an axial direction end surface of a salient pole portion where the winding wire is applied and an axial direction end portion of a slot outer peripheral portion. At the outside of the insulator, an insulating paper which is bended to match the shape of the slot outer peripheral portion is disposed. In this insulation structure, the insulator and the insulating paper are overlapped in a certain length in the axial direction.